Ortho Dx: Abduction weakness after shoulder dislocation

A 68-year-old woman presents 3 weeks after sustaining a left shoulder dislocation after a fall at her home. At that time, a closed reduction was performed in the emergency department, and the arm was placed in a sling immobilizer. Postreduction radiographs show a reduced glenohumeral joint with no evidence of fracture. The patient denies any history ...